硫磺样品在微波消解仪中经硝酸消解,用石墨炉原子吸收光谱法测定其中的铁含量。以1 g·L-1硝酸镁溶液(10 μL)作为基体改进剂,灰化温度为1 200 ℃,原子化温度为2 000 ℃。铁的质量浓度在3.0~25.0 μg·L-1范围内与其吸光度呈线性关系,方法的检出限(3s/k)为0.5 μg·L-1。对工业硫磺样品进行测定,测定值的相对标准偏差(n=6)为2.2%。用标准加入法进行回收试验,计算得回收率在99.5%~101%之间。

Sample of sulfur was digested with nitric acid using microwave digestion method. The content of Fe in the sample solution was determined by GF-AAS. Solution of 1 g·L-1 magnesium nitrate (10 μL) was used as matrix modifier. The ashing temperature was 1 200 ℃ and the atomization temperature was 2 000 ℃. Linear relationship between values of absorbance and mass concentration of Fe was kept in the range of 3.0-25.0 μg·L-1, with detection limit (3s/k) of 0.5 μg·L-1. Precision of the method was tested at the sample of industrial sulfur, value of RSD (n=6) found was 2.2%. Test for recovery was performed by standard addition method, giving recovery in the range of 99.5%-101%.